Redis

# Set a cache entry with 5-minute TTL
redis-cli SET user:1001:profile '{"name":"Alice","role":"admin"}' EX 300

# Retrieve the cached value
redis-cli GET user:1001:profile

# Check remaining TTL
redis-cli TTL user:1001:profile

Rate Limiting with Sorted Sets

# Add request timestamp to sorted set
redis-cli ZADD rate:user:1001 1710000000 "req1"

# Count requests in the last 60 seconds
redis-cli ZRANGEBYSCORE rate:user:1001 1709999940 1710000000

# Remove expired entries
redis-cli ZREMRANGEBYSCORE rate:user:1001 0 1709999940

Best Practices

1. Use namespaced keys - Format as service:entity:id:field (e.g., app:user:1001:session)
2. Always set TTL - Prevent memory leaks from stale data; use EX/PX on SET
3. Avoid large keys - Split hashes over 1MB; use SCAN instead of KEYS in production
4. Choose persistence wisely - RDB for snapshots (fast restart), AOF for durability (every write)
5. Secure production - Require password (requirepass), bind to private IPs, disable FLUSHALL

Keywords

redis, cache, caching, 缓存, data structures, 数据结构, pub/sub, sentinel, cluster, 主从, 集群, rate limiting, session store, Lua scripting